kibana/test/interactive_setup_api_integration/fixtures/tls_tools.ts

/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the "Elastic License
 * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
 * Public License v 1"; you may not use this file except in compliance with, at
 * your election, the "Elastic License 2.0", the "GNU Affero General Public
 * License v3.0 only", or the "Server Side Public License, v 1".
 */

import tls from 'tls';

export async function getElasticsearchCaCertificate(host: string, port: string) {
  let peerCertificate = await new Promise<tls.DetailedPeerCertificate>((resolve, reject) => {
    const socket = tls.connect({ host, port: Number(port), rejectUnauthorized: false });
    socket.once('secureConnect', () => {
      const cert = socket.getPeerCertificate(true);
      socket.destroy();
      resolve(cert);
    });
    socket.once('error', reject);
  });

  while (
    peerCertificate.issuerCertificate &&
    peerCertificate.fingerprint256 !== peerCertificate.issuerCertificate.fingerprint256
  ) {
    peerCertificate = peerCertificate.issuerCertificate;
  }

  return peerCertificate;
}